1. FIELD OF THE INVENTION
The present invention relates to a steering wheel, specifically, to a steering wheel furnished with a relay mechanism comprising slip rings and contact pins whose tips come in contact with the slip rings, to segmented slip rings for use in the steering wheel, and to a method of disposing the segmented slip rings.
2. DESCRIPTION OF THE RELATED ART
In recent years, audio equipment for vehicles, a computer for drive or the like tends to be assembled in a car. Also, switches for operating the computer for drive or the like are disposed on a pad portion of a steering wheel.
In this case, with reference to FIG. 39, there is provided, as a relay mechanism between the pad portion 916 of the steering wheel and a column portion 918, a multiplex transmission circuit utilizing an optical communication means in which a light emitting element is disposed on the pad portion 916 while a photo detector on the column portion 918.
In such a relay mechanism, as shown in FIG. 39, a pad portion 916 has provided thereon switches 930, a transmission side remote control IC 931, an electric signal-optical signal transducing circuit 932, and a power supply circuit 933. A signal relay portion 901 includes the above mentioned electric signal-optical signal transducing circuit 932, a light emitting circuit 934, a photo detector circuit 935, a signal regenerating circuit 936. A column portion 918 has disposed thereon a waveform shaping circuit 937, a receiving side remote control IC 938, an output interface 939, and a power supply circuit 940 having a battery. Further, a power relay portion 941 is provided between the pad portion 916 and the column portion 918.
By operating the switches 930 on the pad portion 916, the transmission side remote control IC 931, which is supplied with power from the power supply circuit 933, operates. Next, a plurality of electric signals are transduced into optical signals through the electric signal-optical signal transducing circuit 932. The light emitting circuit 934 emits light signals on the basis of the above light signals. At the same time, the photo detector circuit 935 receives the light signals, and the signal regenerating circuit 936 retransduces them into electric signals. Then, the waveform shaping circuit 937 shapes the electric signals into the original pulse waves. Thereafter, the same pulse waves are transmitted to the output interface 939 through the receiving side remote control IC 938 thereby to actuate electric devices or actuators.
However, the above relay mechanism needs the multiplex transmission circuit with a resultant complicated structure and high production cost.